The One shopping mall in Tsim Sha Tsui denies it is the city's coldest mall and says its neighbours give shoppers a cooler welcome.

The South China Morning Post recorded temperatures as low as 21.3 degrees on the fourth floor of The One, well below the 24-to-26 degrees Celsius target set in a government-sponsored energy saving charter, to which 100 malls agreed last month. The One did not sign up.

The two higher floors of the mall also failed to meet the charter's target, with temperatures ranging between 21.4 and 23.6 degrees.

The One, developed by Chinese Estates Holdings, was the coldest among 25 malls surveyed by the Post - 18 of which agreed to the charter.

But the operator of the mall, which opened in 2010, insists that when it comes to the town's coldest malls - it is certainly not the one. It said its internal temperature record for the month showed the mall was at between 22 and 25 degrees.

The mall sent operatives to its local competitors, K11 and i-Square, to check out temperature readings. They found the average temperature at K11 was 23.1 degrees, and i-Square 23 degrees, both lower than The One's 23.6 degrees as measured by the mall operator.

'We find our temperature similar and not the coldest among the malls,' the operator said.

A spokesman said the mall had neither been 'asked nor invited' to join the charter. 'In our view, self-discipline is more important than signing any charter,'' he said.

The Post found the coldest temperature at i-Square, at the junction of Peking Road and Nathan Road, was 21.8 degrees. i-Square did not respond to queries while K11 refused to comment on The One's findings.

Some mall tenants say they have their reasons to stay cool.

Temperatures at iPlanet Lifestyles in The Metropolis in Hung Hom were just 21.8 degrees, but owner Wong Chau said he was just thinking of his employees. 'I have one employee who is scared of sweating,' he said.